origins, as well as the modifications of airflows, generated on larger atmospheric scales, by the topography and the cover of the surface. - In agricultural meteorology, the effects of the kinetic energy transfer of wind to the plant/soil system as well the effects of its mass transfer on the energy and water balance are of interest. 2.5.12 Units By its physical nature two magnitudes are required when describing wind its velocity and the direction from which it blows. - Windspeed is usually indicated in m/sec, km/h, or knots (= 1 nautical mile/h), but occasionally the nonlinear Beaufort scale is used, which refers "forces" from 0 to 12 to the effects of wind on smoke, trees or water surfaces. - The direction from which the wind blows is either given in • accordance with the geographical directions (e.g. N,E,S,W)
